Articoli di riviste: "Knee"

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Wilding, Christopher P., Martyn Snow e Lee Jeys. "Which factors affect the ability to kneel following total knee arthroplasty? An outpatient study of 100 postoperative knee replacements". Journal of Orthopaedic Surgery 27, n. 3 (1 settembre 2019): 230949901988551. http://dx.doi.org/10.1177/2309499019885510.

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Background: Kneeling is an important activity of daily living, holding social, religious and occupational value. Following total knee replacement (TKR), many patients report they are unable to kneel or have been advised not to kneel. Methods: We observed 100 consecutive knee replacements in 79 patients attending outpatient clinic at a minimum 5 months post-TKR. The patients were asked to fill out a questionnaire detailing whether they were able to kneel prior to their knee replacement and whether they thought they were able to kneel since their knee replacement. The patients were then asked to kneel on a padded examination couch and then onto a pillow on the floor for 15 s. Degree of flexion achievable was also recorded. Results: Of the knees with patella resurfacing, 78.6% were able to kneel compared to only 45.6% knees with native patellae. Two-tailed Fisher’s exact test showed this difference to be statistically significant ( p = 0.001). The χ 2 analysis showed that those patients with an achievable flexion of angle of greater than 100° were significantly more likely to be able to kneel than those with a flexion angle of less than 100° ( p = 0.0148). Comparing posterior cruciate ligament (PCL) retaining against PCL sacrificing implants, there was no statistically significant difference in kneeling ability ( p = 0.541). Conclusion: Kneeling remains an important function in patients undergoing TKR, with patella resurfacing significantly improving the likelihood of a patient being able to kneel.

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Fahlman, Lissa, Emmeline Sangeorzan, Nimisha Chheda e Daphne Lambright. "Older Adults without Radiographic Knee Osteoarthritis: Knee Alignment and Knee Range of Motion". Clinical Medicine Insights: Arthritis and Musculoskeletal Disorders 7 (gennaio 2014): CMAMD.S13009. http://dx.doi.org/10.4137/cmamd.s13009.

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This study describes knee alignment and active knee range of motion (ROM) in a community-based group of 78-year old adults (n = 143) who did not have radiographic evidence of knee osteoarthritis in either knee (KL < 2). Although knee malalignment is a risk factor for knee osteoarthritis, most women and men had either valgus or varus alignments. Notably, no men were valgus in both knees. Women with both knees valgus had significantly greater body mass index ( P > 0.001) than women with varus or straight knees. Men and women with valgus or varus knee alignments had generally lower ROM than individuals with both knees straight. In summary, this study highlights the complex relationships among knee alignment, ROM, body mass index, and gender in elderly adults without radiographic knee osteoarthritis.

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Mohd Nizlan, Nasir, Fauzah Abd Ghani e Rohaman Tasarib. "Acute Post-Traumatic Locked Knee - An Unmasking of a Rare Knee Disorder". Malaysian Journal of Medicine and Health Sciences 18, n. 5 (15 settembre 2022): 215–17. http://dx.doi.org/10.47836/mjmhs.18.5.29.

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Locked knees are commonly caused by meniscal tears, floating osteochondral bodies, ruptured anterior cruciate ligament (ACL) stump, or other mechanical origins in the knee. Some locked knees occur spontaneously, while in most cases, by a preceding knee trauma. Locked knees are rarely caused by a pathological growth in the knee. More unusually is the occurrence of locked knee caused by a pre-existing pathological entity after a traumatic event. We report a rare case of locking in the knee by a pre-existing knee condition presented only after trauma to the knee. This case emphasizes that locking in the knee can be caused by a pathology that may be asymptomatic until it is revealed by a traumatic event.

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Ismail, Shiek Abdullah, Milena Simic, Lucy J. Salmon, Justin P. Roe, Leo A. Pinczewski, Richard Smith e Evangelos Pappas. "Side-to-Side Differences in Varus Thrust and Knee Abduction Moment in High-Functioning Individuals With Chronic Anterior Cruciate Ligament Deficiency". American Journal of Sports Medicine 47, n. 3 (10 dicembre 2018): 590–97. http://dx.doi.org/10.1177/0363546518812883.

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Background: There is evidence that frontal plane knee joint motion plays a crucial role in the pathogenesis of knee osteoarthritis, yet investigation of individuals with chronic anterior cruciate ligament–deficient (ACLD) knees remains sparse. Purpose: To investigate (1) if individuals with chronic ACLD knees demonstrate higher biomechanical measures of medial knee load as compared with their anterior cruciate ligament–intact (ACLI) knees, (2) if differences in static knee alignment of the ACLD knee will demonstrate a difference in the magnitude of biomechanical measures of medial knee load when compared with the ACLI knee, and (3) the side-to-side concordance of varus thrust among individuals with chronic ACLD knees. Study Design: Descriptive laboratory study. Methods: Participants were sourced from a metropolitan orthopaedic surgeon group. Those who met the inclusion criteria and agreed to participate underwent a 3-dimensional gait analysis assessment to measure knee adduction moment (KAM), knee flexion moment (KFM), KAM peaks, KAM impulse, and varus thrust. Frontal plane knee static alignment was measured with a digital inclinometer fixed to medical calipers. The participants were divided according to their static knee alignment (neutral, varus, and valgus) for subgroup analysis. Peak knee angular velocity and frontal plane knee angle were used to establish if a participant was walking with a knee thrust. An individual was deemed to have knee thrust during gait if the largest frontal plane knee movement coincided with the peak knee angular velocity that occurred within the first 30% of stance phase. Results: Forty-five participants were recruited. The mean (SD) time from injury was 34.5 (55.6) months. ACLD knees did not demonstrate higher mean KAM and KFM ( P > .5) or early-stance peak KAM ( P = .3-.8) and KAM impulse ( P = .3-.9) as compared with ACLI knees as a whole group or when the varus, neutral, and valgus alignment subgroups were investigated separately. Twenty-three percent (n = 9) of the participants had a varus thrust at the ACLD or ACLI knee, 44% (n = 4) had a varus thrust at the ACLD knee, and 22% (n = 2) had varus thrust at both knees. Conclusion: There were no side-to-side differences in mean KAM and KFM and early-stance peak KAM and KAM impulse among high-functioning individuals with chronic unilateral ACLD knees. There was a low prevalence of varus thrust among high-functioning individuals with chronic unilateral ACLD knees.

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Agarwal, A., S. Miller, W. Hadden, L. Johnston, W. Wang, G. Arnold e RJ Abboud. "Comparison of gait kinematics in total and unicondylar knee replacement surgery". Annals of The Royal College of Surgeons of England 101, n. 6 (luglio 2019): 391–98. http://dx.doi.org/10.1308/rcsann.2019.0016.

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Introduction This study is aimed to compare kinematic gait data of patients who have undergone total and unicondylar knee replacement. Materials and methods This single-surgeon retrospective cohort study evaluated 13 patients with unilateral total knee arthroplasty (TKA) and 14 unicondylar knee arthroplasty (UKA). Gait analysis was carried out using a Vicon motion analysis system. The limits of knee flexion during stance phase, at heel strike and at loading response were measured. Results The total range of motion of the UKA knees was significantly greater than the TKA knees. UKA knees exhibited significantly greater knee extension during the stance phase than the TKA knees. Unlike TKA, UKA knees demonstrated improved knee flexion during the gait cycle when compared to the contralateral non-operated knee. The hips also demonstrated near normal hip flexion in UKA patients. Predictably, UKA knees had significantly greater varus compared with TKA in the coronal plane. Spatiotemporal variables demonstrated similar walking speed and step length to aid a fair comparison between knee replacement groups. Conclusions The UKA knees moved more physiologically in the sagittal plane with a greater range of motion during gait. Despite having a stiff gait pattern, the patients undergoing TKA demonstrated a more neutral alignment in the coronal plane. Neither type of knee arthroplasty restored knee kinematics to those of the non-operated side.

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Ekholm, J., R. Nisell, U. P Arborelius, C. Hammerberg e G. Németh. "Load on knee joint structures and muscular activity during lifting." Journal of Rehabilitation Medicine 16, n. 1 (4 giugno 2020): 1–9. http://dx.doi.org/10.2340/16501977841619.

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The load on the knee joints during lifting has been less studied than low back load. Healthy subjects lifted a 12.8-kg box from floor to table-level in three different ways; 1) with straight knees, 2) with bent knees and the box in front of the knees, and 3) with bent knees and the box between the knees. The loading moment of force about the bilateral knee axis was calculated by means of a computerized static sagittal plane model. Electromyography was recorded from quadriceps and ischiocrural muscles. The beginning of the flexed-knee lifts caused a flexing loading knee moment of about 50 Nm and a knee angle of 90 degrees. Straight-knee lifts gave all through the lift an extending loading moment. During the final phase of all lifts there was an extending loading knee moment of about 55 Nm and a knee angle of 0 degrees. The three lifts were compared and discussed from a biomechanical and ergonomical point of view.

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Amin, Raj M., Vikram Vasan e Julius K. Oni. "Kneeling after Total Knee Arthroplasty". Journal of Knee Surgery 33, n. 02 (2 gennaio 2019): 138–43. http://dx.doi.org/10.1055/s-0038-1676801.

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AbstractThe ability to kneel is one of the many patient goals after total knee arthroplasty (TKA). Few studies have addressed patients' ability to kneel after TKA as a primary outcome. Given the altered biomechanics of the knee after TKA, the various implant designs, and multiple surgical approaches, there is a need to further understand the patient's kneeling ability after TKA. We evaluated the available literature on this topic to help to guide postoperative care recommendations. Biomechanical data show that the load borne by the patellofemoral joint is elevated significantly at all flexion angles, whereas tibiofemoral articulation pressures are elevated only at 90 to 120 degrees of flexion. However, these increased pressures are rarely borne by prosthetic knees because patients often avoid kneeling after TKA. In patients who do kneel after surgery, data show that increased range of motion promotes improved kneeling performance. Targeted interventions to encourage kneeling after TKA, including preoperative education, have not shown an ability to increase the frequency with which patients kneel after TKA. Reasons for patient avoidance of kneeling are multifaceted and complex. There is no biomechanical or clinical evidence contraindicating kneeling after TKA. There are insufficient data to recommend particular prosthetic designs or surgical approaches to maximize kneeling ability after surgery. Musculoskeletal health care providers should continue to promote kneeling to allow patients to achieve maximum clinical benefit after TKA.

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Zhou, Xinhua, Min Wang, Chao Liu, Liang Zhang e Yixin Zhou. "Total knee arthroplasty for severe valgus knee deformity". Chinese Medical Journal 127, n. 6 (20 marzo 2014): 1062–66. http://dx.doi.org/10.3760/cma.j.issn.0366-6999.20132488.

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Background Primary total knee arthroplasty (TKA) in severe valgus knees may prove challenging, and choice of implant depends on the severity of the valgus deformity and the extent of soft-tissue release. The purpose of this study was to review 8 to 11 years (mean, 10 years) follow-up results of primary TKA for varient-III valgus knee deformity with use of different type implants. Methods Between January 2002 and January 2005, 20 women and 12 men, aged 47 to 63 (mean, 57.19±6.08) years old, with varient-III valgus knees underwent primary TKA. Of the 32 patients, 37 knees had varient-III deformities. Pie crusting was carefully performed with small, multiple inside-out incisions, bone resection balanced the knee in lieu of soft tissue releases that were not used in the series. Cruciate-retaining knees (Gemini MKII, Link Company, Germany) were used in 13 knees, Genesis II (Simth & Nephew Company, USA) in 14 knees, and hinged knee (Endo-Model Company, Germany) in 10 knees. In five patients with bilateral variant-III TKAs, three patients underwent 1-stage bilateral procedures, and two underwent 2-stage procedures. All implants were cemented and the patella was not resurfaced. The Hospital for Special Surgery (HSS) knee score was assessed. Patients were followed up from 8 to 11 years. Results The mean HSS knee score were improved from 50.33±11.60 to 90.06±3.07 (P <0.001). The mean tibiofemoral alignment were improved from valgus 32.72°±9.68° pre-operation to 4.89°±0.90° post-operation (P <0.001). The mean range of motion were improved from 93.72°±23.69° pre-operation to 116.61±16.29° post-operation (P <0.001). No patients underwent revision. One patient underwent open reduction and internal fixation using femoral condylar plates for supracondylar femoral fractures secondary to a fall at three years. Three patients developed transient peroneal nerve palsies, which resolved within nine months. Two patients developed symptomatic deep vein thrombosis that was managed with rivaroxaban and thrombo-embolic deterrent stockings. There was no incidence of pulmonary embolism. Postoperative patient satisfaction was 80.7±10.4 points in the groups. Prosthetic survival rate was 100% at mean 10 years postoperative. Conclusions Not only hinged implants can be successfully used in variant-III valgus knees. As our results show, if proper ligament balancing techniques are used and proper ligament balance is attained, the knee may not require the use of a more constrained components. Our results also present alternative implant choices for severe knee deformities.

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Nachtnebl, Luboš, Vasileios Apostolopoulos, Michal Mahdal, Lukáš Pazourek, Pavel Brančík, Tomáš Valoušek, Petr Boháč e Tomáš Tomáš. "Implant Preference and Clinical Outcomes of Patients with Staged Bilateral Total Knee Arthroplasty: All-Polyethylene and Contralateral Metal-Backed Tibial Components". Journal of Clinical Medicine 12, n. 23 (30 novembre 2023): 7438. http://dx.doi.org/10.3390/jcm12237438.

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Numerous studies have compared metal-backed components (MBTs) and all-polyethylene tibial components (APTs), but none of them specifically analysed the clinical results and the overall patient preference in patients who had undergone a staged bilateral knee replacement. The purpose of this study is to compare clinical results, perceived range of motion, and overall implant preference among patients who had undergone staged bilateral knee replacement with an APT and contralateral knee replacement with MBTs. A dataset of 62 patients from a single centre who underwent staged bilateral TKA between 2009 and 2022 was selected and retrospectively analysed. Tibial component removal was performed in three knees overall, all of which had MBTs. The mean measured Knee Score (KS) of knees with APTs was 78.37 and that of contralateral knees with MBTs was 77.4. The mean measured Function (FS) of knees with APTs was 78.22, and that of contralateral knees with MBs was 76.29. The mean flexion angle of knees with APTs was 103.8 and that for knees with MBTs was 101.04 degrees. A total of 54.8% of the patients preferred the knee that received APTs over contralateral MBTs. In our cohort, TKA with an APT in one knee and an MBT in the contralateral knee recorded similar clinical results and perceived ranges of motion. Patients in general preferred the knee that received an APT over contralateral knee with an MBT.

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Lee, SeungHoon, YunSeong Choi, JaeHyuk Lee, HeeDong Lee, JungRo Yoon e ChongBum Chang. "Valgus Arthritic Knee Responds Better to Conservative Treatment than the Varus Arthritic Knee". Medicina 59, n. 4 (17 aprile 2023): 779. http://dx.doi.org/10.3390/medicina59040779.

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Background and Objectives: Clinically, it is beneficial to determine the knee osteoarthritis (OA) subtype that responds well to conservative treatments. Therefore, this study aimed to determine the differences between varus and valgus arthritic knees in the response to conservative treatment. We hypothesized that valgus arthritic knees would respond better to conservative treatment than varus arthritic knees. Materials and Methods: Medical records of 834 patients who received knee OA treatment were retrospectively reviewed. Patients with Kellgren–Lawrence grades III and IV were divided into two groups according to knee alignment (varus arthritic knee, hip-knee-ankle angle [HKA] > 0° or valgus arthritic knee, HKA < 0°). The Kaplan–Meier curve with total knee arthroplasty (TKA) as an endpoint was used to compare the survival probability between varus and valgus arthritic knees at one, two, three, four, and five years after the first visit. A receiver operating characteristic (ROC) curve was used to compare the HKA thresholds for TKA between varus and valgus arthritic knees. Results: Valgus arthritic knees responded better to conservative treatment than varus arthritic knees. With TKA as an endpoint, the survival probabilities for varus and valgus arthritic knees were 24.2% and 61.4%, respectively, at the 5-year follow-up (p < 0.001). The thresholds of HKA for varus and valgus arthritic knees for TKA were 4.9° and −8.1°, respectively (varus: area under the ROC curve [AUC] = 0.704, 95% confidence interval [CI] 0.666–0.741, p < 0.001, sensitivity = 0.870, specificity = 0.524; valgus: AUC = 0.753, 95% CI 0.693–0.807, p < 0.001, sensitivity = 0.753, specificity = 0.786). Conclusions: Conservative treatment is more effective for valgus than for varus arthritic knees. This should be considered when explaining the prognosis of conservative treatment for knees with varus and valgus arthritis.

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Nagai, Kanto, Elmar Herbst, Tom Gale, Yasutaka Tashiro, James J. Irrgang, William Anderst e Freddie H. Fu. "Patient-reported outcome measures following anterior cruciate ligament reconstruction are not related to dynamic knee extension angle". Journal of ISAKOS: Joint Disorders & Orthopaedic Sports Medicine 3, n. 1 (gennaio 2018): 33–37. http://dx.doi.org/10.1136/jisakos-2017-000173.

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ObjectivesControversy still exists on whether knee hyperextension affects the outcome following anterior cruciate ligament reconstruction (ACL-R). Therefore, the purpose of the present study was to determine if maximum knee extension angle of ACL-R knees and contralateral uninjured knees during walking is related to the clinical outcome following ACL-R. It was hypothesised that maximum knee extension angle would not be significantly correlated with patient-reported outcome measures (PROMs) following ACL-R.MethodsForty-two patients (age at surgery: 23±9 years, 23 male and 19 female) underwent unilateral ACL-R. Twenty-four months after surgery, subjects performed level walking on a treadmill while biplane radiographs were acquired at 100 Hz. Three-dimensional tibiofemoral motion was determined using a validated model-based tracking process. Tibiofemoral rotations were calculated from foot strike through early stance. The primary kinematic outcome measure was maximum knee extension angle of ACL-R and contralateral uninjured knees during walking, with positive values indicating hyperextension. The side-to-side difference (SSD) in maximum knee extension angle was calculated by subtracting the angle of the contralateral uninjured knee from that of the ACL reconstructed knee. PROMs (International Knee Documentation Committee Subjective Knee Form, Knee Injury and Osteoarthritis Score and Marx Activity Rating Scale) were obtained at 24 months after surgery. Correlations between PROMs and maximum dynamic knee extension angle in ACL-R and contralateral knee were evaluated (P<0.05).ResultsMaximum knee extension angle during walking was 2.3±4.5° in ACL-R knees and 4.3±4.2° in contralateral uninjured knees at 24 months after surgery, indicating hyperextension during walking on average. SSD in maximum knee extension angle was −2.0±3.7°. No significant correlation was observed between maximum knee extension angle and the PROMs.ConclusionMaximum knee extension angle during walking was not significantly correlated with PROMs, suggesting that clinically, physiologic knee hyperextension can be restored after ACL-R and not adversely affect PROMs.Level of evidenceLevel III.

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Ebied, Ayman M., Hany Elsayed e Osama Gamal. "Sex-specific versus standard posterior cruciate-substituting total knee prosthesis". Egyptian Orthopaedic Journal 56, n. 2 (aprile 2021): 82–88. http://dx.doi.org/10.4103/eoj.eoj_67_21.

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Background The introduction of sex-specific (SS) knee prosthesis designs was an approach to offer more sizing options and is based on the anatomic sex differences. These SS components were though to provide better fitting to female femora and consequently improve the clinical outcome. Materials and methods In the period between February 2011 and March 2013, a prospective superiority randomized controlled clinical trial was conducted to compare the clinical outcome of SS versus the standard posterior stabilized (PS) knee prosthesis in women. The primary outcome measure was the postoperative range of knee flexion, and the secondary outcome measure was the knee function as reflected on the performance of daily activities. The OXFORD Knee Score, Knee Society Score, and Knee Society Score for function were recorded preoperatively and then at 3, 12 months, and annually thereafter. Female patients with degenerative or inflammatory arthritis who were 50 years or older and their knee deformities were totally articular were included. A total of 64 patients with 80 knees were enrolled in this trial, and 40 knees were allocated to each group. Knees in the SS group had total knee arthroplasty using SS knee prosthesis, with SS femoral component (the experimental group), whereas knees in the PS group had standard PS knee design with standard femoral component (the control group). Equal randomization (1 : 1 ratio) was undertaken according to a computer-generated randomization table. Results The mean preoperative knee flexion range of motion (ROM) was 110 and 108° in the SS and PS groups, respectively. At the latest follow-up, the mean postoperative knee flexion ROM was 115 and 113° the SS and PS groups, respectively. The mean improvement in the knee flexion ROM in both groups was 5° (range: 0–25), with no statistically significant difference between the two groups. All knees except one had full extension. No statistically significant difference was observed between the two groups when the OXFORD Knee Score, the Knee Society Score, and the Knee Society Score for function were compared. Conclusion No clinical advantage was observed in the ROM or function between knees that received SS knee prosthesis when compared with those who received PS knee implants. The SS total knee arthroplasty though designed to provide better fitting to the female distal femur does not provide any clinical advantage over the standard PS knee prosthesis. A logic question is whether a separate implant is required for women or modifications to the knee prostheses geometry and more sizes are required to accommodate all patients? Level of evidence Level II.

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Hiranaka, Takafumi, Yuichi Hida, Takaaki Fujishiro, Tomoyuki Kamenaga, Kenichi Kikuchi, Ryo Yoshikawa, Shotaro Tachibana e Koji Okamoto. "Approximately 30% of Functioning Anterior Cruciate Ligaments Are Sacrificed for Knee Arthroplasty". Journal of Knee Surgery 33, n. 07 (25 marzo 2019): 655–58. http://dx.doi.org/10.1055/s-0039-1683928.

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AbstractThe anterior cruciate ligament (ACL) plays an important role in knee kinematics. Unicompartmental knee arthroplasty (UKA) preserves the ACL, an advantage over total knee arthroplasty (TKA), where it is sacrificed. This study aims to evaluate how often functional ACLs are sacrificed in arthroplasty. The type of arthroplasty (TKA or UKA) and condition of the ACL were studied in a total of 1,586 knees in 1,052 patients who underwent knee arthroplasties. Of 1,586 knees, TKA was performed on 653 knees (41%) and UKA on 933 knees (59%). The ACL was functioning in 77% of all knees. Of the TKA knees, the ACL was functioning in 357 knees (55%). Of these, around 30% of the functioning ACLs were sacrificed to perform TKA. To improve postoperative patient satisfaction after knee arthroplasty, further study regarding relationship between ACL preservation and clinical outcome will be required.

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HARMAN, MELINDA K., SCOTT A. BANKS, BENJAMIN J. FREGLY, W. GREGORY SAWYER e W. ANDREW HODGE. "BIOMECHANICAL MECHANISMS FOR DAMAGE: RETRIEVAL ANALYSIS AND COMPUTATIONAL WEAR PREDICTIONS IN TOTAL KNEE REPLACEMENTS". Journal of Mechanics in Medicine and Biology 05, n. 03 (settembre 2005): 469–75. http://dx.doi.org/10.1142/s0219519405001588.

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Damage patterns on the articular surface of the proximal tibia, including cartilage degeneration in osteoarthritic knees and damage of polyethylene knee prostheses after total knee replacement, provide information related to knee joint biomechanics and damage mechanisms at the articular surface. This study reports articular damage patterns and knee kinematics assessed in the knees of older subjects, before and after total knee replacement. The damage patterns are used to evaluate computational dynamic contact and tribological models that predict polyethylene damage in a patient-specific total knee replacement model.

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Blaisdell, Jay, e James Talmage. "Rating Knee Impairments". Guides Newsletter 23, n. 1 (1 gennaio 2018): 14–16. http://dx.doi.org/10.1001/amaguidesnewsletters.2018.janfeb04.

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Abstract Workers who kneel for major portions of their workday (eg, floor and roof installers) may be prone to inflammation of the knee bursae and patellofemoral pain. In the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), range-of-motion (ROM) and diagnosis-based impairment (DBI) are the two possible stand-alone methods for rating knee impairment. The ROM method was widely used in previous editions of the AMA Guides, but at present DBI is the method of choice for calculating impairment. To rate knee impairment using the DBI method, the physician first chooses the appropriate diagnosis from the Knee Regional Grid in the AMA Guides, Sixth Edition. Next, the physician chooses the appropriate impairment class for the diagnosis and then selects the appropriate grade modifiers. The physician applies the net adjustment formula to determine lower extremity impairment and finally converts the final lower extremity impairment to whole person impairment. Two or more conditions often are found in the knees and require causation analysis in which the physician should choose the single causally related diagnosis that will yield the highest impairment rating. Modifiers should be chosen based on reliable findings that have not been used previously to assign either the diagnosis or impairment class. The ROM method can be used to select the physical examination grade modifier or as a stand-alone rating if the physician offers a rationale that is supported by the AMA Guides.

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WISE, BARTON L., DAVID T. FELSON, MARGARET CLANCY, JINGBO NIU, TUHINA NEOGI, NANCY E. LANE, JEAN HIETPAS et al. "Consistency of Knee Pain and Risk of Knee Replacement: The Multicenter Osteoarthritis Study". Journal of Rheumatology 38, n. 7 (15 aprile 2011): 1390–95. http://dx.doi.org/10.3899/jrheum.100743.

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Objective.To examine whether the consistency or persistence of knee pain, in addition to its severity, predicts incident total knee replacement (TKR).Methods.The Multicenter Osteoarthritis Study (MOST) is a longitudinal study of persons aged 50 to 79 years with symptomatic knee osteoarthritis or at high risk of disease. Subjects were queried about the presence of knee pain on most days of the previous 30 days (i.e., frequent knee pain; FKP) at 2 timepoints: a telephone screen followed by a clinic visit (median separation 4 weeks). We defined a knee as having “consistent pain” if the subject answered positively to the FKP question at both timepoints, “inconsistent pain” if FKP was positive at only one timepoint, or as “no FKP” if negative at both. We examined the association between consistent FKP and risk of TKR using multiple binomial regression with generalized estimating equations.Results.In 3026 persons (mean age 63 yrs, mean body mass index 30.4), 2979 knees (50%) had no FKP at baseline, 1279 knees (21.5%) had inconsistent FKP, and 1696 knees (28.5%) had consistent FKP. Risk of TKR over 30 months was 0.8%, 2.6%, and 8.8% for knees with no, inconsistent, and consistent FKP, respectively. Relative risks of TKR over 30 months were 1.2 (95% CI 0.6–2.3) and 2.3 (95% CI 1.2–4.4) for knees with inconsistent and consistent FKP, compared with those without FKP. This association was consistent across each level of pain severity on the Western Ontario and McMaster Universities Osteoarthritis Index.Conclusion.Consistency of frequent knee pain is associated with an increased risk of TKR independently of knee pain severity.

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Iriuchishima, Takanori, e Keinosuke Ryu. "A Comparison of Rollback Ratio between Bicruciate Substituting Total Knee Arthroplasty and Oxford Unicompartmental Knee Arthroplasty". Journal of Knee Surgery 31, n. 06 (25 luglio 2017): 568–72. http://dx.doi.org/10.1055/s-0037-1604445.

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AbstractThe purpose of this study was to compare the rollback ratio in bicruciate substituting (BCS) total knee arthroplasty (TKA) and bicruciate-retaining Oxford unicompartmental knee arthroplasty (UKA). In this study, 64 subjects (64 knees) undergoing BCS-TKA (Journey II: Smith and Nephew) and 50 subjects (50 knees) undergoing Oxford UKA (Zimmer-Biomet holdings, Inc., IN) were included. Approximately 6 months after surgery, and when the subjects had recovered their knee range of motion, following the Laidlow's method, lateral radiographic imaging of the knee was performed with active full knee flexion. The most posterior tibiofemoral contact point was measured for the evaluation of femoral rollback (rollback ratio). Flexion angle was also measured using the same radiograph and the correlation of rollback and flexion angle was analyzed. As a control, radiographs of the asymptomatic contralateral knees of subjects undergoing Oxford UKA were evaluated (50 knees). The rollback ratios of the BCS-TKA, Oxford UKA, and control knees were 37.9 ± 4.9, 35.7 ± 4.2, and 35.3 ± 4.8% respectively. No significant difference in rollback ratio was observed among the three groups. The flexion angles of the BCS-TKA, Oxford UKA, and control knees were 123.8 ± 8.4, 125.4 ± 7.5, and 127 ± 10.3 degrees, respectively. No significant difference in knee flexion angle was observed among the three groups. Significant correlation between rollback ratio and knee flexion angle was observed (p = 0.002; Pearson's correlation coefficient = − 0.384). BCS-TKA showed no significant difference in rollback ratio when compared with control knees and Oxford UKA knees. The BCS-TKA design is likely to reproduce native anterior cruciate ligament and posterior cruciate ligament function, and native knee rollback.

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Kivimäki, J., H. Riihimäki e H. Alaranta. "Knee disorders in carpet and floor layers and painters. Part I. Isometric knee extension and flexion torques". Journal of Rehabilitation Medicine 26, n. 2 (1 aprile 1994): 91–95. http://dx.doi.org/10.2340/1650197719942629195.

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Knee morbidity, knee extension torque and knee flexion torque were examined among 168 actively working carpet and floor layers and 146 painters. The study included a questionnaire concerning knee disorders and knee symptoms, a clinical examination of the knees and measurement of isometric knee extension and flexion torque. Knee accidents were reported more frequently by carpet and floor layers than by painters. Tenderness of the knees was noted to an equal extent in the two groups. Knee extension torques gradually decreased by increasing age among carpet and floor layers, but not among painters. Body weight and thigh girth were not related to age among carpet and floor layers, but gradually increased with age among painters. Analysis of covariance showed that the torques were most consistently related to thigh girth and age. In addition, the right knee extension torque was related to occupation and tenderness of the patellofemoral joint; the left knee extension torque was related to the knee pain index. These results suggest that occupational kneeling and internal derangement of the knee affect thigh muscles among actively working house builders.

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Kivimäki, J., H. Riihimäki e H. Alaranta. "Knee disorders in carpet and floor layers and painters. Part I. Isometric knee extension and flexion torques". Journal of Rehabilitation Medicine 26, n. 2 (1 giugno 1994): 91–95. http://dx.doi.org/10.2340/16501977949195.

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Abstract (sommario):

Knee morbidity, knee extension torque and knee flexion torque were examined among 168 actively working carpet and floor layers and 146 painters. The study included a questionnaire concerning knee disorders and knee symptoms, a clinical examination of the knees and measurement of isometric knee extension and flexion torque. Knee accidents were reported more frequently by carpet and floor layers than by painters. Tenderness of the knees was noted to an equal extent in the two groups. Knee extension torques gradually decreased by increasing age among carpet and floor layers, but not among painters. Body weight and thigh girth were not related to age among carpet and floor layers, but gradually increased with age among painters. Analysis of covariance showed that the torques were most consistently related to thigh girth and age. In addition, the right knee extension torque was related to occupation and tenderness of the patellofemoral joint; the left knee extension torque was related to the knee pain index. These results suggest that occupational kneeling and internal derangement of the knee affect thigh muscles among actively working house builders.

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Sava, Manuel-Paul, Alexandra Leica, Felix Amsler, Sotirios Leles e Michael T. Hirschmann. "Only 26% of Native Knees Show an Identical Coronal Functional Knee Phenotype in the Contralateral Knee". Journal of Personalized Medicine 14, n. 2 (9 febbraio 2024): 193. http://dx.doi.org/10.3390/jpm14020193.

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Background: A comprehensive exploration evaluating left-to-right knee symmetry across all anatomical planes utilizing three-dimensional (3D) scans stands absent from the existing body of research. Therefore, the primary objectives of this investigation involved examining potential differences and resemblances in alignment and structure between left and right non-osteoarthritic (native) knees in various planes (coronal, sagittal, and axial) using three-dimensional single-photon emission computed tomography/computed tomography (SPECT/CT) images. Methods: A total of 282 native knees from 141 patients were retrospectively gathered from the hospital’s records. Patients, aged between 16 and 45, who underwent Tc99m-methyl diphosphonate SPECT/CT scans for both knees, adhering to the Imperial Knee Protocol, were included. A statistical analysis was conducted, including 23 knee morphometric parameters, comparing left and right knees, and classifying them based on functional knee phenotypes across the coronal, sagittal, and axial planes. Results: Regarding the functional coronal knee phenotype, 26% of patients (n = 37) exhibited identical phenotypes in both knees (p < 0.001). Significant correlated similarities between the left and right knees were observed in the coronal plane (Pearson’s r = 0.76, 0.68, 0.76, 0.76, p < 0.001) and in several morphometric measures in the sagittal plane (Pearson’s r = 0.92, 0.72, 0.64, p < 0.001). Moderately correlated similarities were noted in the axial plane (Pearson’s r = 0.43, 0.44, 0.43, p < 0.001). Conclusions: Only 26% of native knees exhibit an identical coronal phenotype in their contralateral knee, whereas 67% have the adjacent coronal phenotype. Strongly correlated resemblances were established across various left and right knee morphometric parameters in the coronal, sagittal, and axial planes. These findings could enhance decisions in procedures like total knee arthroplasties or osteotomies, where alignment is key to outcomes, and reveal a potential for future artificial intelligence-driven models to improve our understanding and improve personalized treatment strategies for knee osteoarthritis.

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C, Kavinaya, e Ashuthoshkumar L. "Various Knee Model Measurement Techniques to Find the Knee Geometries". International Journal of Pharmacy and Biomedical Engineering 3, n. 3 (25 dicembre 2016): 4–6. http://dx.doi.org/10.14445/23942576/ijpbe-v3i3p102.

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Computation of knee modeling is a subject-specific techniquethatdefining the zero-load measurements of the cruciate and indemnity ligaments.The dynamic knee simulator was used to test the three carcass knees. The carcass knees also experiencedphysicalsachet of motion testing to discovery their inactivesort of motion in order to regulate the zero-load measurements for everymuscle bundle. Compotation multibody knee representations were shaped for each knee and classical kinematics were likened to investigational kinematics for a replicated walk series. Simple-minded non-linear mechanisminhibition elements were used to characterize cruciate and deposited particles in musclepackages in the knee representations. This learningoriginate that knee kinematics was enormously sensitive to changing of the zero-load measurement. The domino effects also recommendoptimum methods for describing each of the muscle bundle zero-load measurements, irrespective of the subject. These consequencesvalidate the significance ofthe zero-load length when modeling the knee united and verify that physicalcloak of motion dimensions can be usedto determine the passive range of motion of the knee joint. It is also supposed that the method defined here forresponsible zero-load measurement can be used for in vitro or in vivo subject-specific computational models.

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Thilak, Jai, Srivatsa Nagaraja Rao, Vipin Mohan e Balu C. Babu. "Image-based robot assisted bicompartmental knee arthroplasty versus total knee arthroplasty". SICOT-J 8 (2022): 48. http://dx.doi.org/10.1051/sicotj/2022048.

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Objective: To evaluate the short-term clinical outcomes of image-based robot-assisted bicruciate retaining bicompartmental knee arthroplasty and compare it to robot-assisted total knee arthroplasty in the Indian population. Methods: Between December 2018 and November 2019, five patients (six knees) underwent robot-assisted bicompartmental knee arthroplasty (BCKA). These patients were demographically matched with five patients (six knees) who underwent robot-assisted total knee arthroplasty (TKA) during the same period. Clinical outcomes of these twelve knees were assessed in the form of knee society score (KSS) score, Oxford knee score (OKS), and forgotten joint score (FJS) after a minimum follow-up period of 25 months. The data between the two cohorts were compared and analyzed. Results: Scores obtained from both cohorts were subjected to statistical analysis. SPSS software was utilized and the Mann Whitney U-test was utilized to compare the two groups. There was no statistically significant difference found between the two groups in terms of functional outcome. Conclusion: Image-based robot-assisted BCKA is a bone stock preserving and more physiological procedure which can be a promising alternative to patients presenting with isolated arthritis of only two compartments of the knee. Although long-term, larger trials are warranted to establish it as an alternative, our pilot study shows an equally favorable outcome as TKA, making it an exciting new avenue in the field of arthroplasty.

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Kijima, Hiroaki, Naohisa Miyakoshi, Yuji Kasukawa, Yoshinori Ishikawa, Hayato Kinoshita, Kentaro Ohuchi, Masazumi Suzuki et al. "Cut-Off Value of Medial Meniscal Extrusion for Knee Pain". Advances in Orthopedics 2017 (2017): 1–4. http://dx.doi.org/10.1155/2017/6793026.

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Purpose. Medial meniscal extrusion (MME) has attracted attention as an index of knee pain in conjunction with clinical symptoms that could be more useful than the diagnosis of knee osteoarthritis on X-ray. However, the size of MME that would cause knee pain has not been clarified. The aim of the present study was to investigate the cut-off value of MME for knee pain. Methods. A total of 318 knees were evaluated. The presence of current or past knee pain was confirmed by interview. Next, MME was measured using vertical sonographic images of the medial joint spaces during weightbearing. Results. Overall, 71 knees were painful (P-group), and 247 knees were not (N-group). MME was 5.9 ± 1.8 mm in the P-group and 2.9 ± 1.5 mm in the N-group (P<0.0001). Analysis of the receiver operating characteristic curve showed that the cut-off value of MME for knee pain was 4.3 mm, with sensitivity of 0.8451 and specificity of 0.8502. In addition, 64% of knees without pain cases at the time of examination whose MME exceeded this cut-off value had past knee pain. Conclusions. The sensitivity and specificity of MME for knee pain were very high with a cut-off value of 4.3 mm.

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White, Leigh, Nicholas Hartnell, Melissa Hennessy e Judy Mullan. "The Impact of an Intact Infrapatellar Fat Pad on Outcomes after Total Knee Arthroplasty". Advances in Orthopedic Surgery 2015 (16 novembre 2015): 1–6. http://dx.doi.org/10.1155/2015/817906.

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Background. The infrapatellar fat pad (IPFP) is currently resected in approximately 88% of Total Knee Arthroplasties (TKAs). We hypothesised that an intact IPFP would improve outcomes after TKA. Methods. Patients with an intact IPFP participated in this cross-sectional study by completing two surveys, at 6 and 12 months after TKA. Both surveys included questions regarding kneeling, with the Oxford Knee Score also included at 12 months. Results. Sixty patients participated in this study. At 6 and 12 months, a similar number of patients were able to kneel, 40 (66.7%) and 43 (71.7%), respectively. Fifteen (25.0%) patients were unable to kneel due to knee pain at 6 months; of these, nine (15%) were unable to kneel at 12 months. Moreover, at 12 months, 90.0% of the patients reported minimal or no knee pain. There was no correlation between the inability to kneel and knee pain (p=0.13). There was a significant correlation between the inability to kneel and reduced overall standardised knee function scores (p=0.02). Conclusions. This was the first study to demonstrate improved kneeling and descending of stairs after TKA with IPFP preservation. These results in the context of current literature show that IPFP preservation reduces the incidence of knee pain 12 months after TKA.

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Anand, TS, e S. Sujatha. "A method for performance comparison of polycentric knees and its application to the design of a knee for developing countries". Prosthetics and Orthotics International 41, n. 4 (18 luglio 2016): 402–11. http://dx.doi.org/10.1177/0309364616652017.

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Background:Polycentric knees for transfemoral prostheses have a variety of geometries, but a survey of literature shows that there are few ways of comparing their performance.Objectives:Our objective was to present a method for performance comparison of polycentric knee geometries and design a new geometry.Study design:In this work, we define parameters to compare various commercially available prosthetic knees in terms of their stability, toe clearance, maximum flexion, and so on and optimize the parameters to obtain a new knee design.Methods:We use the defined parameters and optimization to design a new knee geometry that provides the greater stability and toe clearance necessary to navigate uneven terrain which is typically encountered in developing countries.Results:Several commercial knees were compared based on the defined parameters to determine their suitability for uneven terrain. A new knee was designed based on optimization of these parameters. Preliminary user testing indicates that the new knee is very stable and easy to use.Conclusion:The methodology can be used for better knee selection and design of more customized knee geometries.Clinical relevanceThe method provides a tool to aid in the selection and design of polycentric knees for transfemoral prostheses.

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Reddy, K. Vijaya Bhaskar, N. Brahma Chary e Birru Sumanth. "A study on functional outcome of posterior cruciate ligament substituted total knee arthroplasty". International Journal of Research in Orthopaedics 7, n. 6 (26 ottobre 2021): 1161. http://dx.doi.org/10.18203/issn.2455-4510.intjresorthop20214182.

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Background: Total knee replacement surgery is considered as a treatment of choice in patients with advanced arthritis, especially in patients where conservative treatment has been failed. Total knee replacement gives good pain relief, functional improvement of knee and correction of deformity.Methods: This is study of 39 patients following total knee arthroplasty, who were operated between August 2017 and March 2020 at MNR Medical College and Hospital, Sangareddy. They were followed up for a minimum period of 1 year and evaluated using oxford knee scoring system. Oxford knee score is designed specifically for measuring outcomes in knee arthroplasty. There were 14 right knees, 10 left knees, 15 bilateral knees.Results: There was a significant functional improvement of knee in patients and we had achieved excellent results, out of 39 patients and 4 patients had post op suprapatellar fullness, which was relieved with medications for 3 weeks and 2 patients (2 knees) without no signs of immediate post-operative period, developed infection after 6 months followed which underwent staged revision total knee replacement. The outcome categories based on oxford knee scoring system: excellent (40-48), good (30-39), fair (20-29) and poor (0-19).Conclusions: It is difficult to balance the knee with retention of posterior cruciate ligament, whereas posterior cruciate ligament substituting total knee replacement gives reproducible and good results, hence it is the preferred mode of management.

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Unat, Beytullah, e G. Karakurum. "Midterm Outcomes of Posterior Cruciate Ligament Substituting Total Knee Arthroplasty". Annals of Medical Research 30, n. 11 (2023): 1. http://dx.doi.org/10.5455/annalsmedres.2023.09.250.

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Abstract (sommario):

Objective: In the present study, it is aimed to retrospectively investigate and present the midterm results of the cases with posterior cruciate ligament (PCL) substituting total knee arthroplasty. Materials and Methods: In this study, we included a total of 61 patients with 80 knees who underwent PCL-substituting total knee arthroplasty between July 2006 and June 2012. Results: 52 patients were female and 9 were male. The mean age of patients was 65.4 (42-85) years and the mean follow up period was 32.6 (12-72) months. Patients were evaluated according to the American Knee Society Score for knee score and knee functional score. Radiological evaluation was performed according to Total Knee Arthroplasty Radiological Evaluation criteria. Knee score was 38-71 (mean 43.7) prior to the surgery and 78-100 (mean 95) subsequently. 69 knee (86,25%) had perfect knee scores and 11 knee (13.75%) had good scores. Functional score was 10-60 (mean 35.08) prior to the surgery and 60-100 (mean 82.2) subsequently. In the evaluation according to the functional knee score, we obtained perfect results in 45 knee (56.25%) and good results in 29 knees (36.25%) and moderate results in 6 knees (7.5%). Patients had a mean 9.7o varus (8o valgus – 20o varus) prior to the surgery and mean 4.75o valgus (2o varus – 10o valgus) alignment was obtained subsequently to surgery. In 1 case revision arthroplasty was performed due to late deep infection. In 1 case insert replacement was performed due to insert fracture due to trauma. As a result of our PCL substituting total knee arthroplasty applications, we obtained 86.25%perfect knee score and 56.25%perfect functional score. Conclusion: PCL substituting total knee arthroplasty is a favorable orthopedic surgical intervention when preformed with adequate preoperative preparations and cautious surgical techniques with appropriate patient choice.

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Hildebrand, Kevin A., Michael Holmberg e Nigel Shrive. "A New Method to Measure Post-Traumatic Joint Contractures in the Rabbit Knee". Journal of Biomechanical Engineering 125, n. 6 (1 dicembre 2003): 887–92. http://dx.doi.org/10.1115/1.1634285.

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Abstract (sommario):

A new device and method to measure rabbit knee joint angles are described. The method was used to measure rabbit knee joint angles in normal specimens and in knee joints with obvious contractures. The custom-designed and manufactured gripping device has two clamps. The femoral clamp sits on a pinion gear that is driven by a rack attached to a materials testing system. A 100 N load cell in series with the rack gives force feedback. The tibial clamp is attached to a rotatory potentiometer. The system allows the knee joint multiple degrees-of-freedom (DOF). There are two independent DOF (compression-distraction and internal-external rotation) and two coupled motions (medial-lateral translation coupled with varus-valgus rotation; anterior-posterior translation coupled with flexion-extension rotation). Knee joint extension-flexion motion is measured, which is a combination of the materials testing system displacement (converted to degrees of motion) and the potentiometer values (calibrated to degrees). Internal frictional forces were determined to be at maximum 2% of measured loading. Two separate experiments were performed to evaluate rabbit knees. First, normal right and left pairs of knees from four New Zealand White (NZW) rabbits were subjected to cyclic loading. An extension torque of 0.2 Nm was applied to each knee. The average change in knee joint extension from the first to the fifth cycle was 1.9deg±1.5degmean±sd with a total of 49 tests of these eight knees. The maximum extension of the four left knees (tested 23 times) was 14.6deg±7.1deg, and of the four right knees (tested 26 times) was 12.0deg±10.9deg. There was no significant difference in the maximum extension between normal left and right knees. In the second experiment, nine skeletally mature NZW rabbits had stable fractures of the femoral condyles of the right knee that were immobilized for five, six or 10 weeks. The left knee served as an unoperated control. Loss of knee joint extension (flexion contracture) was demonstrated for the experimental knees using the new methodology where the maximum extension was 35deg±9deg, compared to the unoperated knee maximum extension of 11deg±7deg, 10 or 12 weeks after the immobilization was discontinued. The custom gripping device coupled to a materials testing machine will serve as a measurement test for future studies characterizing a rabbit knee model of post-traumatic joint contractures.

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Norouzi, Sadegh, Fateme Esfandiarpour, Ali Shakourirad, Reza Salehi, Mohammad Akbar e Farzam Farahmand. "Rehabilitation after ACL Injury: A Fluoroscopic Study on the Effects of Type of Exercise on the Knee Sagittal Plane Arthrokinematics". BioMed Research International 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/248525.

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Abstract (sommario):

A safe rehabilitation exercise for anterior cruciate ligament (ACL) injuries needs to be compatible with the normal knee arthrokinematics to avoid abnormal loading on the joint structures. The objective of this study was to measure the amount of the anterior tibial translation (ATT) of the ACL-deficient knees during selective open and closed kinetic chain exercises. The intact and injured knees of fourteen male subjects with unilateral ACL injury were imaged using uniplanar fluoroscopy, while the subjects performed forward lunge and unloaded/loaded open kinetic knee extension exercises. The ATTs were measured from fluoroscopic images, as the distance between the tibial and femoral reference points, at seven knee flexion angles, from 0° to 90°. No significant differences were found between the ATTs of the ACL-deficient and intact knees at all flexion angles during forward lunge and unloaded open kinetic knee extension (). During loaded open kinetic knee extension, however, the ATTs of the ACL deficient knees were significantly larger than those of the intact knees at 0° (). It was suggested that the forward lunge, as a weight-bearing closed kinetic chain exercise, provides a safer approach for developing muscle strength and functional stability in rehabilitation program of ACL-deficient knees, in comparison with open kinetic knee extension exercise.

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Heinrichs, Christian H., Dominik Knierzinger, Hannes Stofferin e Werner Schmoelz. "Validation of a novel biomechanical test bench for the knee joint with six degrees of freedom". Biomedical Engineering / Biomedizinische Technik 63, n. 6 (27 novembre 2018): 709–17. http://dx.doi.org/10.1515/bmt-2016-0255.

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AbstractA novel biomechanical test bench has been developed for in-vitro evaluation of the knee joint. The test bench allows the kinematics of the knee joint to be studied in all six degrees of freedom. Flexion-extension knee movements are induced by quadriceps and hamstring muscle forces simulated by five pneumatic cylinders. The kinematics of the knee and the actively applied muscle forces are measured simultaneously. The aim of this study was to validate the sensitivity and reproducibility of this novel test bench. Four fresh frozen human knees were tested three times, each with seven flexion-extension cycles between 5° and 60°. After the native knees had been tested, the posterior cruciate ligament and then the lateral collateral ligament were dissected. The injured knees were tested in identical conditions [3×(7×5°–60°)] in order to evaluate whether the test bench is capable of detecting differences in knee kinematics between a native state and an injured one. With regard to reproducibility, the novel test bench showed almost perfect agreement for each specimen and for all states and flexion angles. In comparison with the native knees, the injured knees showed significant differences in knee kinematics. This validated novel test bench will make it possible to investigate various knee pathologies, as well as current and newly developed treatment options.

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Hollman, John H., Robert H. Deusinger, Linda R. Van Dillen e Matthew J. Matava. "Knee Joint Movements in Subjects Without Knee Pathology and Subjects With Injured Anterior Cruciate Ligaments". Physical Therapy 82, n. 10 (1 ottobre 2002): 960–72. http://dx.doi.org/10.1093/ptj/82.10.960.

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Abstract Background and Purpose. Although weight-bearing (WB) exercise and increased hamstring muscle activity may contribute to knee joint stability in knees with an injured anterior cruciate ligament (ACL), the relationship among ACL integrity, muscle activity, and joint surface motion is not fully understood. The purpose of this study was to investigate whether knee joint rolling and gliding movements and electromyographic (EMG) activity differed between subjects with injured ACLs and subjects without knee pathology. Subjects. Fifteen subjects with injured ACLs (9 men and 6 women; mean age=26 years, SD=7, range=18–36) and 15 age- and sex-matched subjects without knee pathology (9 men and 6 women; mean age=25 years, SD=6, range=18–36) participated in the study. Methods. Sagittal-plane knee joint rolling and gliding movements and lower-extremity EMG activity were measured during non-weight-bearing (NWB) and WB movements. Mixed-model analyses of variance were conducted to analyze rolling and gliding and EMG data. Results. During NWB knee extension, greater joint surface gliding occurred in knees with injured ACLs at full knee extension. During WB knee extension, greater gliding occurred in knees with injured ACLs throughout the range of motion tested. No differences in EMG activity occurred between groups. Discussion and Conclusion. The results suggest that, in the absence of increased hamstring muscle activity, anterior tibial displacement is not reduced in knees with injured ACLs during WB movement.

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Nielsen, Emil Toft, Kasper Stentz-Olesen, Sepp de Raedt, Peter Bo Jørgensen, Ole Gade Sørensen, Bart Kaptein, Michael Skipper Andersen e Maiken Stilling. "Influence of the Anterolateral Ligament on Knee Laxity: A Biomechanical Cadaveric Study Measuring Knee Kinematics in 6 Degrees of Freedom Using Dynamic Radiostereometric Analysis". Orthopaedic Journal of Sports Medicine 6, n. 8 (1 agosto 2018): 232596711878969. http://dx.doi.org/10.1177/2325967118789699.

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Abstract (sommario):

Background: An anterior cruciate ligament (ACL) rupture often occurs during rotational trauma to the knee and may be associated with damage to extracapsular knee rotation–stabilizing structures such as the anterolateral ligament (ALL). Purpose: To investigate ex vivo knee laxity in 6 degrees of freedom with and without ALL reconstruction as a supplement to ACL reconstruction. Study Design: Controlled laboratory study. Methods: Cadaveric knees (N = 8) were analyzed using dynamic radiostereometry during a controlled pivotlike dynamic movement simulated by motorized knee flexion (0° to 60°) with 4-N·m internal rotation torque. We tested the cadaveric specimens in 5 successive ligament situations: intact, ACL lesion, ACL + ALL lesion, ACL reconstruction, and ACL + ALL reconstruction. Anatomic single-bundle reconstruction methods were used for both the ACL and the ALL, with a bone-tendon quadriceps autograft and gracilis tendon autograft, respectively. Three-dimensional kinematics and articular surface interactions were used to determine knee laxity. Results: For the entire knee flexion motion, an ACL + ALL lesion increased the mean knee laxity ( P < .005) for internal rotation (2.54°), anterior translation (1.68 mm), and varus rotation (0.53°). Augmented ALL reconstruction reduced knee laxity for anterior translation ( P = .003) and varus rotation ( P = .047) compared with ACL + ALL–deficient knees. Knees with ACL + ALL lesions had more internal rotation ( P < .001) and anterior translation ( P < .045) at knee flexion angles below 40° and 30°, respectively, compared with healthy knees. Combined ACL + ALL reconstruction did not completely restore native kinematics/laxity at flexion angles below 10° for anterior translation and below 20° for internal rotation ( P < .035). ACL + ALL reconstruction was not found to overconstrain the knee joint. Conclusion: Augmented ALL reconstruction with ACL reconstruction in a cadaveric setting reduces internal rotation, varus rotation, and anterior translation knee laxity similar to knee kinematics with intact ligaments, except at knee flexion angles between 0° and 20°. Clinical Relevance: Patients with ACL injuries can potentially achieve better results with augmented ALL reconstruction along with ACL reconstruction than with stand-alone ACL reconstruction. Furthermore, dynamic radiostereometry provides the opportunity to examine clinical patients and compare the recontructed knee with the contralateral knee in 6 degrees of freedom.

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Driban, Jeffrey B., Grace H. Lo, Charles B. Eaton, Lori Lyn Price, Bing Lu e Timothy E. McAlindon. "Knee Pain and a Prior Injury Are Associated with Increased Risk of a New Knee Injury: Data from the Osteoarthritis Initiative". Journal of Rheumatology 42, n. 8 (1 giugno 2015): 1463–69. http://dx.doi.org/10.3899/jrheum.150016.

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Abstract (sommario):

Objective.We explored whether knee pain or a history of knee injury were associated with a knee injury in the following 12 months.Methods.We conducted longitudinal knee-based analyses among knees in the Osteoarthritis Initiative. We included both knees of all participants who had at least 1 followup visit with complete data. Our first sets of exposures were knee pain (chronic knee symptoms and severity) at baseline, 12-month, 24-month, and 36-month visits. Another exposure was a history of injury that we defined as a self-reported injury at any time prior to baseline, 12-month, 24-month, or 36-month visit. The outcome was self-reported knee injury during the past year at 12-month, 24-month, 36-month, and 48-month visits. We evaluated the association between ipsilateral and contralateral knee pain or history of injury and a new knee injury within 12 months of the exposure using generalized linear mixed model for repeated binary outcomes.Results.A knee with reported chronic knee symptoms or ipsilateral or contralateral history of an injury was more likely to experience a new knee injury in the following 12 months than a knee without chronic knee symptoms (OR 1.84, 95% CI 1.57–2.16) or prior injury (prior ipsilateral knee injury: OR 1.81, 95% CI 1.56–2.09. Prior contralateral knee injury: OR 1.43, 95% CI 1.23–1.66).Conclusion.Knee pain and a history of injury are associated with new knee injuries. It may be beneficial for individuals with knee pain or a history of injury to participate in injury prevention programs.

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Freitas, Priscilla Da Silva, Caroline Cabral Robinson, Rodrigo Py Gonçalves Barreto, Milton Antonio Zaro, Luis Henrique Telles Da Rosa e Marcelo Faria Silva. "Infrared thermography in adolescents with Osgood-Schlatter Disease". ConScientiae Saúde 12, n. 4 (28 gennaio 2014): 513–18. http://dx.doi.org/10.5585/conssaude.v12n4.4319.

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Abstract (sommario):

Introduction: Thermography has been used to monitor musculoskeletal disorders, but no study has assessed thermal patterns of anterior tibial tuberosity inflammation that occurs in Osgood-Schlatter Disease (OSD). Objective: To investigate the patterns of knee temperature in adolescents with and without OSD. Methods: Twenty adolescents were separated into two groups: one comprising individuals with OSD and a control in which none had OSD. An infrared image of the knees was recorded after 15 minutes of acclimatization in a temperature-controlled environment, and the maximum absolute knee temperature and the temperature difference (T) between knees were obtained. Results: The maximum knee temperature in the OSD group was significantly higher (p = 0.008) than the highest recorded knee temperature in the control group. The T between knees was significantly higher (p = 0.007) in the OSD group than in the control group. Conclusion: Adolescents with OSD present knee thermal asymmetry and hyper-radiant patterns in the affected knee, these alterations are prominent enough to be detected thermographically through infrared imaging.

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Fosco, M., M. Filanti, L. Amendola, L. M. Savarino e D. Tigani. "Total knee arthroplasty in stiff knee compared with flexible knees". MUSCULOSKELETAL SURGERY 95, n. 1 (9 marzo 2011): 7–12. http://dx.doi.org/10.1007/s12306-011-0099-6.

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Miller, S., A. Agarwal, WB Haddon, L. Johnston, G. Arnold, W. Wang e RJ Abboud. "Comparison of gait kinetics in total and unicondylar knee replacement surgery". Annals of The Royal College of Surgeons of England 100, n. 4 (aprile 2018): 267–74. http://dx.doi.org/10.1308/rcsann.2017.0226.

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Abstract (sommario):

Introduction The aim of this study was to compare kinetical data from gait analysis of patients who have undergone total and uni-condylar knee replacement. Materials and methods Thirteen patients with unilateral total knee arthroplasty (TKA) and 13 unicondylar knee arthroplasty (UKA), were included, all performed by the same surgeon more than one year prior. The Vicon gait analysis system was used. Statistical power was calculated using SPSS. Results No significant difference was found in the spatiotemporal parameters of gait and survival years of the knee prosthesis between the two groups. The UKA group was found to have significantly larger moments than the TKA group in knee adduction on the operated side and knee flexion moment on the unoperated side during the loading phase. The maximum and minimum sagittal plane moments of the operated sides in the TKA group were significantly lower than the unoperated side. The difference was most significant at pre-swing. The maximum and minimum moments on the operated sides in the UKA group were significantly lower for the knee flexion and adduction moments when compared with the unoperated side and were most prevalent during the loading phase. Conclusions These results are relevant in terms of prosthesis wear. The TKA knees had smaller magnitude moments than the UKA knees in the sagittal and coronal planes. This could explain the higher revision rates for UKA. In both groups, the non-operated knees had significantly larger moments than the operated knees, which implies that after unilateral knee replacement of either type, the non-operated knee is being put under greater stress.

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Kijima, Hiroaki, Shin Yamada, Koji Nozaka, Hidetomo Saito e Yoichi Shimada. "Relationship between Pain and Medial Meniscal Extrusion in Knee Osteoarthritis". Advances in Orthopedics 2015 (2015): 1–4. http://dx.doi.org/10.1155/2015/210972.

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Purpose. In knee osteoarthritis, the degree of pain varies despite similar imaging findings. If there were quantitative findings related to the pain of knee osteoarthritis, it could be used for diagnosis or screening. The medial meniscal extrusion was investigated as a candidate quantitative finding related to the pain of knee osteoarthritis.Methods. Seventy-six knees of 38 patients (mean age, 73 years) who received intra-articular injections of hyaluronic acid into unilateral knees at the time of diagnosis of knee arthritis were investigated. Cartilage thickness of the femoral medial condyle and medial meniscal extrusion of bilateral knees were measured by ultrasonography. Thirty-eight knees that had hyaluronic acid injections were compared with 38 other side knees from the same patients as the control group.Results. The average cartilage thicknesses of the knees with pain that received intra-articular injections and the knees without pain that received no injections were 1.02 and 1.05 mm, respectively (P=0.6394). On the other hand, the average medial meniscal extrusions of the knees with and without pain were 7.58 and 5.88 mm, respectively (P=0.0005); pain was associated with greater medial meniscal extrusions.Conclusion. Medial meniscal extrusion is a quantitative finding related to the pain of knee osteoarthritis.

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McAuliffe, MJ, G. Garg, JA Roe, A. Vakili, SL Whitehouse e RW Crawford. "How balanced is the knee when we start a total knee replacement?" Orthopaedic Journal of Sports Medicine 5, n. 5_suppl5 (1 maggio 2017): 2325967117S0016. http://dx.doi.org/10.1177/2325967117s00162.

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Objectives: Optimal coronal plane alignment for total knee arthroplasty (TKA) remains controversial. Understanding the pre-operative soft tissue status is important for optimizing the soft tissue envelope during TKA. The purpose of this study was to define the corrected, neutral (“pre-disease”) HKAA of end stage osteoarthritic knees prior to TKA and from this point measure the medial and lateral laxity of varus and valgus knees in maximum extension, 20 and 90° of flexion prior to TKA. Methods: We conducted an observational cohort study. During surgery, the lower limb was manipulated using computer navigation, prior to surgical releases, whilst observing the joint to ensure congruence to allow the limb weight-bearing axis to pass through the knee center in maximum extension, 20° and 90° of flexion. Coronal plane laxity was measured as medial and lateral displacement from this point and compared to published values for healthy subjects. Results: The corrected, neutral HKAA in 89 knees in maximum extension prior to TKA was -1.22° +/- 1.4°. The corrected HKAA in maximum extension was within +/- 3° of 0° in 91.0% of patients. 12.8% (10/78) of varus knees displayed a medial contracture. Of these 10 knees, five also displayed abnormal lateral laxity. In maximum extension, 19.2% (15/78) of knees had abnormally increased lateral laxity. 10 of these 15 knees did not have a medial contracture. The remaining 5 knees with increased lateral laxity or 6.4% (5/78) displayed a medial contracture. Lateral laxity increased significantly with increasing varus deformity. Medial laxity did not significantly decrease when comparing varus deformity of 5 -10° versus >10°. 29 Valgus knees were examined. In maximum extension and 20° of flexion 27.6% of subjects (8/29) and 6.9% (2/29) of subjects respectively had a lateral contracture. On the medial side abnormally increased laxity was seen in 40.7% (11/27) in maximum extension; 75% (21/28) in 20° and 0% in 90° of flexion. On the lateral side abnormally increased laxity was seen in 3.7% (1/27) in maximum extension; 3.6% (1/27) in 20° of flexion and 72.4% in 90° of flexion. Conclusion: Varus and valgus knees did not record a corrected, neutral HKAA at the opposite end of the 0 +/-3° range. Optimal TKA alignment might be better and more specifically defined by the corrected neutral axis of each knee. The majority of varus knees with deformity of up to 15° have neither a medial contracture nor abnormal lateral laxity when referenced to the neutral axis of the knee. Lateral laxity is a more consistent feature of the varus knee. In the valgus OA knee a lateral contracture is not present in most patients and typically only present in maximum extension. The pattern then reverses to an abnormal increase in lateral laxity in flexion for many subjects. The pattern on the medial side is for maximum soft tissue disturbance in 20° of flexion before normalising in 90° of flexion. These findings demonstrate potentially problematic scenarios for balancing the valgus OA knee. The patterns of contracture and laxity found are variable and correlate poorly to deformity.

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Vo, Minh Tu, Ambrish Singh, Tao Meng, Jasveen Kaur, Alison Venn, Flavia Cicuttini, Lyn March et al. "Prevalence and Clinical Significance of Residual or Reconverted Red Bone Marrow on Knee MRI". Diagnostics 11, n. 9 (25 agosto 2021): 1531. http://dx.doi.org/10.3390/diagnostics11091531.

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Background: Residual/reconverted red bone marrow (RBM) in adult knees is occasionally observed on routine knee magnetic resonance imaging (MRI). We aimed to identify its prevalence, distribution, and associations with lifestyle factors, knee structural abnormalities, and knee symptoms in young adults. Methods: Participants (n = 327; aged = 31–41 years) were selected from the Childhood Determinants of Adult Health (CDAH) knee study. They underwent T1-weighted and proton-density-weighted fat-suppressed MRI scans of knees. Residual/reconverted RBM in distal femur and proximal tibia were graded semi-quantitatively (grades: 0–3) based on the percentage area occupied. Knee structural abnormalities were graded semi-quantitatively using previously published MRI scoring systems. Knee symptoms (pain, stiffness, and dysfunction) were assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scale during CDAH knee study (year: 2008–2010) and at 6–9-year follow-up during the CDAH-3 study (year: 2014–2019). Associations between definite RBM (grade ≥ 2) and lifestyle factors, knee symptoms, and structural abnormalities were described using log-binomial regressions. Results: Definite RBM was seen in females only, in 29 out of 154 cases (18.8%), with femoral involvement preceding tibial involvement. Definite RBM was associated with increased BMI (PR = 1.09/kg/m2; 95% CI: 1.03, 1.16), overweight status (PR = 2.19; 95% CI: 1.07, 4.51), and WOMAC knee pain (PR = 1.75; 95% CI: 1.11, 2.74) in cross-section analysis. However, there was no association between RBM and knee-pain after seven years (PR = 1.15; 95% CI: 0.66, 2.00). There were no associations between RBM and knee structural abnormalities. Conclusion: Presence of definite RBM in young adult knees was observed in females only. Definite RBM was associated with overweight measures, and the modest association with knee pain may not be causally related.

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40

Harter, Rod A., Louis R. Osternig e Kenneth M. Singer. "Knee Joint Proprioception Following Anterior Cruciate Ligament Reconstruction". Journal of Sport Rehabilitation 1, n. 2 (maggio 1992): 103–10. http://dx.doi.org/10.1123/jsr.1.2.103.

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This study evaluated knee joint position sense in the ACL-reconstructed and contralateral normal knees of 48 male and female subjects (M age 27.6 ± 6.9 yrs). Subjects were blindfolded and tested on their ability to actively reproduce five passively placed knee positions at 5° intervals between 35 and 15° of knee flexion. Mean algebraic target angle error and mean absolute error values were measured in degrees. The grand mean absolute error for the postsurgical knees at all positions was 5.4 ± 3.2°, compared with 5.2 ± 2.7° for the normal contralateral knees. There were no significant differences in knee joint position sense between the postsurgical and normal contralateral limbs at any of the five positions tested. Pivot shift, anterolateral rotatory instability, and Lachman test results were poorly correlated with knee joint position sense. The results suggest that if knee joint position sense was indeed disrupted by ACL injury and reconstructive surgery, related sensory mechanisms compensated for any proprioceptive loss prior to the minimum 2-yr postsurgical follow-up period employed in our study.

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Pirato, Francesco, Federica Rosso, Federico Dettoni, Davide Edoardo Bonasia, Matteo Bruzzone e Roberto Rossi. "How to manage a native stiff knee". EFORT Open Reviews 9, n. 5 (1 maggio 2024): 363–74. http://dx.doi.org/10.1530/eor-24-0034.

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Knee stiffness is a widely known and worrying condition in several postoperative knees. Less is known about native stiff knee. The aim of this manuscript is to summarize the available literature on native stiff knee epidemiology, classification and treatment. In 1989 stiff knee was defined as a knee with less than 50° of total range of motion. If range of motion is <30°, it is defined as an ankylosed knee. Knee stiffness can be divided into three main types: flexion contractures, extension contractures, and combined contractures. Different risk factors have been associated to native stiff knee and grouped into modifiable or not modifiable. Furthermore, risk factors can be divided into patients’ related no patients’-related. Different treatment modalities can be indicated to treat knee stiffness, including manipulation under anesthesia (MUA), arthroscopic and open surgical release. When stiffness is associated with articular disruption TKA represent an option. TKA in native stiff knee can be challenging for the surgeon. Implant’s choice and knee exposure are the first steps. In some cases, additional release and extensive can be considered. A stepwise approach and careful preoperative planning are mandatory to obtain long-term satisfactory outcomes. Native stiff knee is a rare but invalidating condition. Different treatment modalities have been proposed as treatment. However, considering that it is frequently associated to sever arthritis, TKA can be an option in painful stiff knees. Nature of knee stiffness necessitates a customized approach to ensure successful management and achieve satisfying outcomes.

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Artul, Suheil, Fadi Khazin, Jeries Hakim e George Habib. "Ultrasonographic Findings in a Large Series of Patients with Knee Pain". Journal of Clinical Imaging Science 4 (30 agosto 2014): 45. http://dx.doi.org/10.4103/2156-7514.139735.

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Background: Musculoskeletal ultrasound (MSKUS) is becoming more and more popular in the evaluation of different musculoskeletal abnormalities. The aim of this retrospective study was to document the prevalence and spectrum of MSKUS findings at the painful knee. Materials and Methods: All the studies of MSKUS that were performed for the evaluation of knee pain during the previous 2 years at the Department of Radiology in Nazareth hospital were reviewed. Demographic and clinical parameters including age, gender, side, and MSKUS findings were documented. Results: Two hundred and seventy-six patients were included in the review. In 21 of them, both knees were evaluated at the same setting (total number of knees evaluated was 297). One hundred and forty-four knees were of the left side. Thirty-three pathologies were identified. 34% of the studies were negative. The most common MSKUS findings were medial meniscal tear (MMT) (20%), Baker's cyst (BC) (16%), and osteoarthritis (OA) (11%). Only one knee of all the knees evaluated in our study showed synovitis. Fifty-three knees (18% of all the knees evaluated) had more than one imaging finding, mosty two and while some had three findings. The most common combination of findings was MMT and BC (8 knees), MMT with OA (8 knees), and MMT with fluid (6 knee). In 67% of the patients who had simultaneous bilateral knee evaluation, at least one knee had no abnormal findings and in 43%, both knees were negative. Conclusions: MSKUS has the potential for revealing huge spectrum of abnormalities. In nearly 90% of the positive studies, degenerative/mechanical abnormalities were reported, with MMT, BC, and osteoarthritic changes being the most common.

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JONES, RICHARD K., GRAHAM J. CHAPMAN, ANDREW H. FINDLOW, LAURA FORSYTHE, MATTHEW J. PARKES, JAWAD SULTAN e DAVID T. FELSON. "A New Approach to Prevention of Knee Osteoarthritis: Reducing Medial Load in the Contralateral Knee". Journal of Rheumatology 40, n. 3 (15 gennaio 2013): 309–15. http://dx.doi.org/10.3899/jrheum.120589.

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Objective.Few if any prevention strategies are available for knee osteoarthritis (OA). In those with symptomatic medial OA, the contralateral knee may be at high risk of disease, and a reduction in medial loading in that knee might prevent disease or its progression there. Our aim was to determine how often persons with medial OA on 1 side had either concurrent or later medial OA on the contralateral side, and whether an intervention known to reduce medial loading in affected knees with medial OA might reduce medial loading in the contralateral knee. Lateral wedge insoles reduce loading across an affected medial knee but their effect on the contralateral knee is unknown.Methods.To determine the proportion of persons with medial knee OA who had concurrent medial contralateral OA or developed contralateral medial OA later, we examined knee radiographs from the longitudinal Framingham Osteoarthritis Study. Then, to examine an approach to reducing medial load in the contralateral knee, 51 people from a separate study with painful medial tibiofemoral OA underwent gait analysis wearing bilateral controlled shoes with no insoles, and then with 2 types of wedge insoles laterally posted by 5°. Primary outcome was the external knee adduction moment (EKAM) in the contralateral knee. Nonparametric CI were constructed around the median differences in percentage change in the affected and contralateral sides.Results.Of Framingham subjects with medial radiograph knee OA, 137/152 (90%) either had concurrent contralateral medial OA or developed it within 10 years. Of those with medial symptomatic knee OA, 43/67 (64%) had or developed the same disease state in the contralateral knee. Compared to a control shoe, medial loading was reduced substantially on both the affected (median percentage EKAM change −4.84%; 95% CI −11.33% to −0.65%) and contralateral sides (median percentage EKAM change −9.34%; 95% CI −10.57% to −6.45%).Conclusion.In persons with medial OA, the contralateral knee is also at high risk of medial OA. Bilateral reduction in medial loading in knees by use of strategies such as lateral wedge insoles might not only reduce medial load in affected knees but prevent knee OA or its progression on the contralateral side.

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Chillakuru, Cherith Reddy, N. Jambu e Akshay Deepak. "A comparison of the proprioception of osteoarthritic knees and post total knee arthroplasty". International Journal of Research in Orthopaedics 3, n. 4 (23 giugno 2017): 781. http://dx.doi.org/10.18203/issn.2455-4510.intjresorthop20172525.

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Background: Proprioception of the knee joint is an important factor for establishing balance, and smooth walking. The effect of arthroplasty on proprioception can be a determinant of post-operative function and subjective feeling of the arthroplasty. We wished to check the status of osteoarthritic knees and how their proprioceptive function is, in comparison to knees post total knee replacement.Methods: We compared 80 unilateral knee replacement patients with their osteoarthritic counterpart in the opposite knee. There was 50% Cruciate Retaining (n =40), Posterior Stabilized 50% (n =40). We assessed the proprioception using threshold to detection of passive motion and conscious awareness of passive joint position.Results: 73.8% (n =59) of patients experienced a better joint position sense, 21% (n =17) had decreased joint position sense and 5% (n =4) had the same, when compared to the contralateral osteoarthritic knee. The mean of threshold to detection of passive motion was 2.16+0.68 for the replaced knees versus 2.72±0.61 for the contralateral osteoarthritic knee.Conclusions: The proprioception of the knees that were replaced with arthroplasties had a better proprioceptive function then the osteoarthritic knees. This further solidifies the reasons to replace the dysfunctional osteoarthritic knee.

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WANG, SHANGCHENG, ZHIHONG LIU, JIANMING FENG, LIANFU DENG e NAIQUAN NIGEL ZHENG. "COMPARING TRANSVERSE PLANE BIOMECHANICS BETWEEN FIXED- AND MOBILE-BEARING TOTAL KNEE ARTHROPLASTY DURING LEVEL WALKING, STAIR NEGOTIATION AND PIVOTING". Journal of Mechanics in Medicine and Biology 19, n. 05 (agosto 2019): 1950028. http://dx.doi.org/10.1142/s0219519419500283.

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Compared with fixed-bearing (FB) total knee arthroplasty (TKA), mobile-bearing (MB) TKA may promote knee rotation and reduce rotational load at bone–implant interface. Unfortunately, this hypothesis has not been examined with neither knee rotation during stance of pivoting nor knee rotational moment during activities other than level walking. This study used 3D motion analysis to obtain the rotation of tibia relative to the femur and knee rotation moment during stance phase of level walking, stair ascent/descent, step and spin turn for 17 FB, 20[Formula: see text]MB and 28 healthy knees. Statistical comparisons revealed that transverse plane biomechanics was similar between MB and FB knees. Compared with healthy knees ([Formula: see text]), both FB ([Formula: see text]) and MB knees ([Formula: see text]) reduced internal rotation during step turn at early stance. During spin turn, FB knees ([Formula: see text] vs. [Formula: see text]) reduced internal rotation at late stance, whereas MB knees ([Formula: see text] versus [Formula: see text]) reduced external rotation at early stance. MB knees (0.064% and 0.126% body weight [Formula: see text] height) had lower peak external rotation moments during early stance phase of both level walking and spin turn than healthy knees (0.108% and 0.238% body weight [Formula: see text] height). Using FB for TKA surgery without bias and step-turn strategy for pivoting were recommended.

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Mourya, Vandana, Mukesh Prasad Kushwaha, Dambar Sah, Shashi Shekhar Prasad Shah e Kaushal Kishor Singh. "Role of Ultrasonography in The Diagnosis of Knee Joint Lesions". Med Phoenix 8, n. 1 (30 luglio 2023): 33–37. http://dx.doi.org/10.3126/medphoenix.v8i1.53622.

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Introduction: Ultrasound can provide clinically useful information on a wide range of pathologic conditions affecting components of the knee joint, including the tendons, ligaments, muscles, synovial space, articular cartilage, nerves and surrounding soft tissues. The advantages of ultrasound include low cost, portability, real-time assessment, and facilitated side-by-side comparisons. The aim of the study was to study the various pathological conditions of painful knee joint by using ultrasound for early diagnosis and prompt therapeutic approach and to evaluate the osteoarthritic changes in the painful knee joint by ultrasound. Materials and Methods: This is a prospective observational study conducted in the Department of Radiology and Orthopedics& trauma surgery, National Medical College & teaching hospital, Birgunj, Parsa, Nepal for the 6 months duration, patients presented with knee joint pathology including swelling, and pain.Patients included in this study was above 20 years with unilateral (single) knee joint pain. With ethical clearance from the Institutional Review Committee of National Medical College and after obtaining the informed consent of the patient, prospective observational study was conducted. All ultrasound assessments were performed using the same machine with a 9 MHz linear transducer of GE Logiq P7 USG machine. A30–45-degree flexion of the knees was standardized by using the same wedge for all ultrasound assessments. Results: This study included 40 symptomatic patients with knee joints pain included in this study. In 40 patients 19 were females (47.5%) and 21 males (52.5%), with ages ranged from 20 to 70 years. Ultrasound findings showed joint effusions in 25 (62.5 %) as most common finding in painful knees,synovial thickening in 17 (42.5 %) knees, Synovitis in 14 (35.0%) and tendinopathy seen in only 1 (2.5%) knee joint pain. Osteoarthritis such as narrow joint space in 4 (10%) knees, marginal osteophytes in 4 (10%) knees, loose bodies in 3 (7.5%) knees, Baker’s cyst in 1 (2.5%) knee. Most common involved age group is 51-60 years with 17 cases followed by 41-50 years in 11 cases. Conclusion: Ultrasound is a simple and reproducible technique for the assessment of knee joint effusion, synovial changes and osteoarthritis related changes.

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Hsieh, Shang-Lin, Tsung-Li Lin, Chih-Hung Hung, Yi-Chin Fong, Hsien-Te Chen e Chun-Hao Tsai. "Clinical and Radiographic Outcomes of Inversed Restricted Kinematic Alignment Total Knee Arthroplasty by Asia Specific (Huang’s) Phenotypes, a Prospective Pilot Study". Journal of Clinical Medicine 12, n. 6 (8 marzo 2023): 2110. http://dx.doi.org/10.3390/jcm12062110.

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Inverse restricted kinematic alignment (irKA) was modified from restricted kinematic alignment for total knee arthroplasty (TKA). This prospective single-center study aimed to evaluate the outcomes of irKA-TKA on all knee subtypes classified by Asia specific (Huang’s) phenotypes. A total of 96 knees that underwent irKA-TKA at one hospital between January 2018 and June 2020 were included, with 15 knees classified in Type 1, nine in Type 2, 15 in Type 3, 47 in Type 4, and 10 in Type 5 by Huang’s phenotypes. Outcomes were knee alignment measures and patient-reported satisfaction evaluated by the Western Ontario and McMaster Universities Arthritis Index (WOMAC) and traditional Chinese version of the Forgotten Joint Score-12 (FJS-12). Follow-up was one year. Type 4 knee was most significantly corrected in all angles by irKA-TKA, followed by Type 2 and 3 knees. Type 5 and 1 knee were only significantly corrected in some angles. The correlation between FJS-12 and WOMAC was good at 6 months (Pearson correlation coefficient (r) = 0.74) and moderate at 6 weeks, 3 months, and 12 months during follow-up (r = 0.37~0.47). FJS-12 and WOMAC displayed comparable hip–knee–ankle angle cut-off value (4.71° vs. 6.20°), sensitivity (70.49% vs. 67.19%), specificity (84.00% vs. 85.71%), and Youden index (54.49% vs. 52.90%) in prediction of good prognosis. In conclusion, irKA-TKA corrects knee alignment in all knee types with increasing satisfaction for one-year follow-up. Knees with presurgical varus deformity are most recommended for irKA-TKA. Both presurgical scores of the traditional Chinese version of FJS-12 and WOMAC predict the prognosis of irKA-TKA.

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Tomite, Takenori, Hidetomo Saito, Toshiaki Aizawa, Hiroaki Kijima, Naohisa Miyakoshi e Yoichi Shimada. "Gait Analysis of Conventional Total Knee Arthroplasty and Bicruciate Stabilized Total Knee Arthroplasty Using a Triaxial Accelerometer". Case Reports in Orthopedics 2016 (2016): 1–6. http://dx.doi.org/10.1155/2016/6875821.

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One component of conventional total knee arthroplasty is removal of the anterior cruciate ligament, and the knee after total knee arthroplasty has been said to be a knee with anterior cruciate ligament dysfunction. Bicruciate stabilized total knee arthroplasty is believed to reproduce anterior cruciate ligament function in the implant and provide anterior stability. Conventional total knee arthroplasty was performed on the right knee and bicruciate stabilized total knee arthroplasty was performed on the left knee in the same patient, and a triaxial accelerometer was fitted to both knees after surgery. Gait analysis was then performed and is reported here. The subject was a 78-year-old woman who underwent conventional total knee arthroplasty on her right knee and bicruciate stabilized total knee arthroplasty on her left knee. On the femoral side with bicruciate stabilized total knee arthroplasty, compared to conventional total knee arthroplasty, there was little acceleration in thex-axis direction (anteroposterior direction) in the early swing phase. Bicruciate stabilized total knee arthroplasty may be able to replace anterior cruciate ligament function due to the structure of the implant and proper anteroposterior positioning.

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Wang, Jianping, Kun Tao, Huanyi Li e Chengtao Wang. "Modelling and Analysis on Biomechanical Dynamic Characteristics of Knee Flexion Movement under Squatting". Scientific World Journal 2014 (2014): 1–14. http://dx.doi.org/10.1155/2014/321080.

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The model of three-dimensional (3D) geometric knee was built, which included femoral-tibial, patellofemoral articulations and the bone and soft tissues. Dynamic finite element (FE) model of knee was developed to simulate both the kinematics and the internal stresses during knee flexion. The biomechanical experimental system of knee was built to simulate knee squatting using cadaver knees. The flexion motion and dynamic contact characteristics of knee were analyzed, and verified by comparing with the data from in vitro experiment. The results showed that the established dynamic FE models of knee are capable of predicting kinematics and the contact stresses during flexion, and could be an efficient tool for the analysis of total knee replacement (TKR) and knee prosthesis design.

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S, Rajesh, Supreeth D R e Hemant K. Kalyan. "Total Knee Arthroplasty in Bilateral Severe Fixed Flexion Deformity: A Case Report". Journal of Karnataka Orthopaedic Association 10, n. 1 (2022): 22–25. http://dx.doi.org/10.13107/jkoa.2022.v10i01.047.

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Background: Severe bilateral Fixed flexion deformity of the knees resulting from irreversible joint damage is a disabling complication of long-standing rheumatoid arthritis, associated with loss of ambulatory ability. While Total knee Arthroplasty is an effective treatment for such patients, it poses significant intra-operative technical demands and challenges with post-operative rehabilitation. Method: We report a case of Severe Fixed flexion deformity of both knees in a 46-year-old male with long-standing rheumatoid arthritis, non-ambulatory since 5 years, treated by sequential total knee arthroplasty. Results: Treating Severe bilateral Fixed flexion deformities in a non-ambulatory patient by sequential total knee Arthroplasty using standard implants yielded complete deformity correction and pain-free restoration of active range of motion in both knees with stable independent ambulation and complete restoration of lower limb function within 3 months of surgery. Conclusion: Our case is particularly remarkable for complete restoration of stable, pain-free restoration of ambulation within 3months in a patient with severe bilateral knee fixed flexion deformities who had been non-ambulatory for 5 years preceding his bilateral sequential total knee arthroplasty. Keywords: Fixed flexion deformity, Total knee arthroplasty, Common peroneal nerve, Rheumatoid arthritis.

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